diff options
| author | Steven Rostedt <rostedt@goodmis.org> | 2025-08-20 14:03:41 -0400 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2025-08-26 09:51:13 +0200 |
| commit | 90942f9fac05702065ff82ed0bade0d08168d4ea (patch) | |
| tree | 0002a5f7e78d1c877f9806121ee4d1eed84eb50d | |
| parent | 153f9e74dec230f2e070e16fa061bc7adfd2c450 (diff) | |
perf: Use current->flags & PF_KTHREAD|PF_USER_WORKER instead of current->mm == NULL
To determine if a task is a kernel thread or not, it is more reliable to
use (current->flags & (PF_KTHREAD|PF_USER_WORKERi)) than to rely on
current->mm being NULL. That is because some kernel tasks (io_uring
helpers) may have a mm field.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250820180428.592367294@kernel.org
| -rw-r--r-- | kernel/events/callchain.c | 6 | ||||
| -rw-r--r-- | kernel/events/core.c | 4 |
2 files changed, 5 insertions, 5 deletions
diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c index cd0e3fc7ed05..5982d18f169b 100644 --- a/kernel/events/callchain.c +++ b/kernel/events/callchain.c @@ -246,10 +246,10 @@ get_perf_callchain(struct pt_regs *regs, bool kernel, bool user, if (user && !crosstask) { if (!user_mode(regs)) { - if (current->mm) - regs = task_pt_regs(current); - else + if (current->flags & (PF_KTHREAD | PF_USER_WORKER)) regs = NULL; + else + regs = task_pt_regs(current); } if (regs) { diff --git a/kernel/events/core.c b/kernel/events/core.c index bade8e0fced7..f880cec0c980 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -7446,7 +7446,7 @@ static void perf_sample_regs_user(struct perf_regs *regs_user, if (user_mode(regs)) { regs_user->abi = perf_reg_abi(current); regs_user->regs = regs; - } else if (!(current->flags & PF_KTHREAD)) { + } else if (!(current->flags & (PF_KTHREAD | PF_USER_WORKER))) { perf_get_regs_user(regs_user, regs); } else { regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; @@ -8086,7 +8086,7 @@ static u64 perf_virt_to_phys(u64 virt) * Try IRQ-safe get_user_page_fast_only first. * If failed, leave phys_addr as 0. */ - if (current->mm != NULL) { + if (!(current->flags & (PF_KTHREAD | PF_USER_WORKER))) { struct page *p; pagefault_disable(); |